Radiant heater

ABSTRACT

A portable heater providing both radiant and forced air heat a closed loop heating element positioned within a substantially oval shaped reflector, The reflector air vent allows air to pass in from a bottom of the reflector, over the closed loop heating element and the reflector. A housing surrounds the reflector and heating element. A blower is located at a lower end of the housing and draws air inward and up between the reflector and the heating element from which it emerges past the heating element. Control knobs for controlling a thermostat and output power level are located at the top surface of the housing.

FIELD OF THE INVENTION

The present invention relates to portable radiant heaters and more particularly to an electrically powered radiant heater incorporating a blower for forcing air across a profile reflector surface and out into a space. The air absorbs heat from the heating elements and surfaces of the reflector, and is discharged forward from the heater, thereby augmenting radiant heating. The reflector is shaped to direct the radiant heat outwardly from the front of the heater.

BACKGROUND OF THE INVENTION

Supplementary heat for limited spaces may be provided by portable heaters. Typically electrical, portable heaters may distribute heat by convection, forced air, radiation, or a combination of these, Radiant heaters have become popular since they are capable of heating solid objects within reach of the radiant heat, but they do not heat ambient air surrounding these objects. Thus, a person in the room or space benefits from the heat, although the air temperature is not greatly increased.

However, only surfaces exposed to the source of radiant heat experience heating. If, for example, a person standing by a radiant heat source turns, or if another person or object is interposed between the standing person and the heat source, the warmed part of the standing person will chill. To even the heating effect, it becomes desirable to both project radiant heat and to warm the air of the space or room.

To provide this benefit, combination radiant and forced air heaters have been proposed in the prior art. U.S. Pat. No, 5,381,509, issued to Thomas H. Mills on Jan. 10, 1995, describes such a combination of forced air and radiant heater. The heater has a reflector plate for projecting radiated heat forwardly out from the heater, and a fan located behind the reflector plate for forcing air upwardly and out from the heater.

U.S. Pat. No. 3,229,070, issued to Orville C. Wells on Jan. 11, 1966, incorporated herein by reference describes a portable forced air and radiant electric heater which illustrates typical features such as manual on-off switch, thermostatic switch for protection against overheating, heating element guard for preventing direct contact by an external object, and fins for directing airflow. The fan draws air down through the center and directs it out the sides over the circular heating rod. The Wells invention acts primarily as a conventional conductive heater where air is the conductive medium.

An industrial convection and radiant heater is shown in U.S. Pat. No. 4,336,442, issued to Eugene W. Starr on Jun. 22, 1982. Due to its industrial application, the direction of radiation and egress of heated air differs from those of the present invention. Because it is handling pressurized heated gas,

U.S. Pat. No. 1,900,956, issued to William W. Somersall on Mar. 14, 1933, sets forth an upright, portable electric heater with air forced out radially at the top. This device humidifies occupied space by heating water contained above the heat source.

U.S. Pat. No. 3,775,590, issued to William Joseph Gartner on Nov. 27, 1973, describes a portable forced air heater which features a fan mounted toward the top of the heater, and which discharges air horizontally and radially from the top of the heater. Unlike the present invention, there is no significant degree of radiant heating provided by this device. Air flow is different in the present invention, passing through a reflector plate absent in the Gartner device. Also, Gartner locates a manual control near the bottom of the heater.

in U.S. Pat. No. 5,092,518, issued to Mituharu Tomioka et al. on Mar. 3, 1992, there is presented a combustion heater which features forced ejection of heated air. The thrust of the invention is to make constant the reach of projected heated air regardless of the amount of heat being dispersed.

A portable radiant heater is shown in U.S. Pat. No. 4,004,128, issued to Carlo Marchesi on Jan. 18, 1977. This heater surrounds a heating element with a thermal mass, which absorbs heat and radiates heat over a period of time extending beyond the period of time during which the heating element is energized.

A radiant heater described in U.S. Pat. No. 4,164,642, issued to Edward A. Ebert, on Aug. 14, 1979, is employed to heat eyeglass frames. A perforated metallic sheet is interposed between the heating element and an eyeglass frame. The metallic sheet absorbs energy of a given wavelength, and retransmits energy of another wavelength. Energy passing unobstructed through the perforations combine with retransmitted energy to assure that radiant energy of different wavelengths strikes the eyeglass frame.

SUMMARY OF THE INVENTION

The present disclosure provides a portable heater for providing radiant and convection heat. The heater includes a housing having an upper end, a lower end, a back portion and a front portion. An air intake is located at bottom of the back portion and a grill is located at the front portion forming an air outlet.

A heating element and reflector are positioned within the housing. The reflector is disposed between the heating element and a back portion of the housing. The reflector has a substantially oval shape, with the heating element being positioned within the reflector, the reflector at least partially surrounding at least of portion of the heating element. The reflector has a front surface capable of projecting radiant heat out of the heater through the grill. The reflector further includes an air vent arranged along a bottom portion thereof.

A blower is mounted within the lower end of the housing. The blower is interposed between the air intake of the back portion of the housing and the air vent in the reflector. The blower operates to propel air across the height of the reflector and the heating element. Electrical circuitry including blower controls is provided in the upper end of the housing. The electrical circuitry supplying power to the blower and the heating element. The heating element can be a closed loop heating element, including two “U” shaped heating elements.

The reflector is substantially oval in shape, forming a race track, having a raised center portion and a curved outside wall. The raised center portion and curved outside wall form a channel into which the heating element is positioned.

The heater provides a two-fold heating function, the heating element providing radiant heat and the blower causes air to pass in through the air vent, between the reflector and the heating element and between the heating element and the grill to expel heated air through the gill.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

FIG. 1 depicts a front perspective view of the portable heater of the present disclosure;

FIG. 2 depicts a rear perspective view of the portable heater;

FIG. 3 depicts a rear view of the portable heater with the base attached thereto

FIG. 4 depicts a side view of the portable heater;

FIG. 5 depicts a front perspective view of the portable heater showing the reflector and heating element;

FIG. 6 depicts a front sectional view of the portable heater;

FIG. 7 depicts a front perspective view of the reflector and heating element of the portable heater;

FIG. 8 depicts a front view of the reflector and heating element of the portable heater

FIG. 9 depicts a horizontal cross sectional view of the reflector and heating element;

FIG. 10 depicts a vertical cross sectional view of the reflector and heating element; and

FIG. 11 depicts an exemplary electrical diagram of a simplified electrical circuit for the portable heater.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawing figures in which like reference designators refer to like elements, there is shown in FIGS. 1 and 2 a radiant heater 10 of the present disclosure. The radiant heater 10 includes a housing 12 have a front portion 14 and a back portion 16. A control panel 18 is positioned on an upper end 20 of the housing 12. The control panel 18 can include an “on/off” switch, blower power control, oscillation, and thermostat. A base 22 is removable affixed to a lower end 24 of the housing 12. A power cord (not shown) fitted with a power plug extends from the housing 12, supplying electrical power from a household electrical receptacle to the heater 10.

The back portion 16 of the housing includes an air intake 32, though which air is drawn into the heater 10, the air intake 32 being located at a bottom of the back portion 16. A pair of attachment clips 25 and 27 are centrally located on the back portion 16, such that the base 22 can be removeable attached to the attachment clips 25 and 27 for shipping. In this configuration, the footprint of the heater 10 is decreased, allowing for smaller packaging. In addition, the cord can be wrapped about clips 25 and 25 for storage.

Referring to FIG. 3, in use, a user removes the heater 10 from the packaging, detaching the base 22 from the back portion 16 of the heater 10. The base 22 is then removeably attached to the lower end 24 of the housing 12.

Referring also to FIGS. 4 and 5, the front portion 14 of the housing 12 includes a grill 26, partially enclosing a reflector 28 and heating element 30. The grill 26 is shaped to be offset a distance “d” from the front portion 14, spacing the grill 26 a distance from the heating element 30. In this manner, air can pass around an object covering at least a position of the grill 26, reducing the radiant heat on the object.

Referring to FIG. 5, a blower 40 is positioned in a bottom portion 24 of the heater 10, below and adjacent to the reflector 28. The reflector 28 includes air vents 44 in fluid communication with the blower 40. In operation, the blower 40 draws air in from the air intake 32 in the back portion 16 of the housing and blows the air into reflector though the reflector air vents 44. The air vents 44 are positioned on a bottom portion 42 of the reflector 28, such that the air from the blower 40 travels between the reflector 28 and the heating element 30 as well as in front of the heating element 30. The blown air can travel the height of the reflector 28 and heating elements 30, the opposite end 48 of the reflector 28 thereby directing the heated air out from the heater 10 through the grill 26.

Referring to FIGS. 6-8, the reflector 28 is shaped is a substantially oval configuration 50 having a raised central potion 52. In this configuration, the reflector 28 forms a “race track” prismatic reflector. Referring also to FIG. 9, a horizontal cross sectional view of the reflector 28, and FIG. 10, a vertical cross sectional view of the reflector 28, the cross sections 54, 56 of the reflector 28 each forms a substantially “W” shape. The cross sectional 54, 56 “W” shapes of the reflector 28 are configured for reflecting the light and transport the heat outwardly from the heater 10 in all directions, allowing the radiated heat energy to heat up a room.

The outside walls 58 of the “W” shaped cross sections 54, 56 act like a “bowl” 60 where the combination of the “W” shaped cross sections 54, 56 and “bowl” 60 keep reflecting the light and heat produced by the heating element 30 until it passes beyond the grill 26. Furthermore, the combination of the “W” shaped cross sections 54, 56 and “bowl” 60 form a channel 62 through which the blown air travels, directing the heat away from the heater 10. The outside wall 58 of the reflector 28 can also be stepped 64, where the stepped walls 64 aid in the distribution of the heated air away from the heater 10.

The combination of the prismatic reflector 28 and the blower 40 provide a two-fold heating function. The prismatic reflector 28 directed the radiated heat energy outwardly from the beater 10 in all directions. The blower 40 forces air across the length of the heating element 30, both between the reflector 28 and the heat element 30, and the heating element 30 and the grill 26, where the shape of the reflector 29 directs the heated air outward from the heater 10.

The heating element 30 can be a closed loop heating element, or be formed from a pair of “U” shaped heating elements 66, 68 electrically connected. The heating element 30 is attached to the reflector 28 by support members 70. The support member 70 space the heating element 30 apart from the reflector 28, allowing the blower 40 to blow air between the reflector 28 and the heating element 30. The support members 70 can be made of a resilient material, allowing the heating element 30 to move with respect to the reflector 28. In this manner the resilient support members 70 can absorb impact energy during transport or a sudden dropping of the heater, thus helping isolate and prevent the damage to the heating element 30.

A reset button 27 is located on the back of the housing 16 and a thermal cut-out switch is mounted on the reflector 28. The location of the cut-out switch aids in the safe functioning of the heater. By placing it on the reflector surface, it is able to detect heat build-up which typically arises from being turned towards a wall or drapery or from towels or articles of clothing hanging nearby.

FIG. 11 shows an exemplary electrical circuitry fur heater 10. Power supplied through cord and plug 80 is signaled by a lit indicator 82 merely indicating that heater 10 is connected to power, and that ordinary precautions pertaining to any energized appliance would be appropriate. Switch 84 offers the choice of levels of power output connected to heating element 30, this being controlled by appropriate diodes 86. The blower 49 is energized in a power level selected by switch 84.

Thermostatic reset switch 86 is an automatic safety device comprising, preferably, a thermally responsive, snap action switch subjected to the heat from the front of the reflector 28. Switch 86 is located in series within the electrical circuitry so as to control all power. Switch 86 has a metallic element which flexes, or snaps, when subjected to a predetermined temperature. Flexure operates switch contacts (not shown), thus breaking electrical continuity at temperatures above the predetermined temperature. At temperatures below the predetermined temperature, the metallic element flexes back to its original position, and switch returns to a normally closed position.

A second lit indicator 88 (caution light) can be included which is placed in parallel with switch 86, and illuminates should switch 86 break contact. This signals that switch 86 has detected and responded to a potentially dangerous high temperature.

Thermostat 90 is manually adjustable, and operates by controlling all power flowing in the electrical circuitry. Thermostat 90 provides the user with control over the temperature at which heater 10 will operate. This control function is separate from the level of power output selected by switch 84. On-off control may be provided either by selecting an appropriate actuating temperature at thermostat 90, or by incorporation of an “off” position in switch 84.

Thermostat 90 can also incorporate a tip-over switch 92. Switch 92 is preferably a pendulum switch, which opens switch contacts when heater 10 is not in its normal, upright position. Switch 92 could comprise a mercury switch or any other suitable switch responsive to inclination of heater 10 from its normal, upright position. As a further safety feature, an over current device 94 is located in series within the electrical circuitry. Device 94 is a fuse or circuit breaker, as desired, selected to break all power responsive to detection of electrical current exceeding a predetermined magnitude.

Thus, it will be seen that both manual controlled switches 84 and 90, and automatic safety devices 86, 92, and 94, all are placed in series so as to control all power flowing within electrical circuitry. This arrangement effectively de-energizes all components, thus assuring safety regardless of the source of a potential fault.

All references cited herein are expressly incorporated by reference in their entirety.

It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims. 

What is claimed is:
 1. A portable heater for providing radiant and convection heat, said heater comprising: a housing including an upper end, a lower end, a back portion and a front portion, the housing further including an air intake located a bottom of the back portion, a grill located in the front portion forming an air outlet; a heating element; a reflector disposed between the heating element and the back portion of the housing, the reflector having a substantially oval shape, where the heating element is positioned within the reflector with the reflector at least partially surrounding at least of portion of the heating element, the reflector having a front surface capable of projecting radiant heat out of the heater through the grill, the reflector including an air vent arranged along a bottom portion of the reflector; a blower mounted within the lower end of the housing, interposed between the air intake and the air vent in the reflector for propelling air across the length of the reflector and the heating element; and electrical circuitry including fan controls, said electrical circuitry supplying power to the blower and the closed loop heating element.
 2. A portable heater as set forth in claim 1, wherein the heating element comprises a closed loop heating element.
 3. A portable heater as set forth in claim 2, wherein the closed loop heating element comprises two “U” shaped heating elements.
 4. A portable heater as set forth in claim 1, wherein the reflector forms a race track prismatic reflector having a raised center portion and a curved outside wall.
 5. A portable heater as set forth in claim 4, wherein the reflector has a substantially “W” shape cross section along a horizontal axis.
 6. A portable heater as set forth in claim 5, wherein the reflector has a substantially “W” shape cross section along a vertical axis.
 7. A portable heater as set forth in claim 5, wherein the outside walls of the reflector are stepped.
 8. A portable heater as set forth in claim 1, wherein the heating element provides radiant heat and the blower causes air to pass in through the air vent, between the reflector and the heating element and between the heating element and the grill.
 9. A portable heater for providing radiant and convection heat, said heater comprising: a housing including an upper end, a lower end, a back portion and a front portion, the housing further including an air intake located a bottom of the back portion, a grill located at the front portion forming an air outlet; a closed loop heating element; a reflector having a raised center portion and a curved outside wall forming a substantially oval channel, the heating element positioned within the oval channel, the reflector having a front surface capable of projecting radiant heat out of the heater through the grill, the reflector including an air vent arranged along a bottom portion of the oval channel; a blower mounted within the lower end of the housing, interposed between the air intake and the air vent in the reflector for propelling air across the length of the oval channel and the heating element; and electrical circuitry including fan controls, said electrical circuitry supplying power to the blower and the closed loop heating element.
 10. A portable heater as set forth in claim 9, wherein the closed loop heating element comprises two “U” shaped heating elements.
 11. A portable heater as set forth in claim 9, wherein the reflector has a substantially “W” shape cross section along a horizontal axis.
 12. A portable heater as set forth in claim 11, wherein the reflector has a substantially “W” shape cross section along a vertical axis.
 13. A portable heater as set forth in claim 9, wherein the outside walls of the reflector are stepped.
 14. A portable heater as set forth in claim 9, wherein the closed loop heating element is affixed to the reflecting with a plurality of support members, the support member spacing the closed loop heating element a distance from the outside wall of the reflector.
 15. A portable heater as set forth in claim 14, wherein the support members are made of a resilient material.
 16. A portable heater as set forth in claim 9, wherein the closed loop heating element provides radiant heat and the blower causes air to pass in through the air vent, between the oval channel of the reflector and the closed loop heating element and between the closed loop heating element arid the grill.
 17. A portable heater for providing radiant and convection heat, said heater comprising: a housing including an upper end, a lower end, a back portion and a front portion; a grill located in the front portion forming an air outlet; a base removeably attached to the lower end, wherein said base is decoupled from lower end of the housing in a shipping configuration, the base being affixed to the back portion in the shipping configuration.
 18. A portable heater for providing radiant and convection heat as set forth in claim 17, further comprising: a heating element; and a reflector disposed between the heating element and the back portion of the housing, the reflector including an air vent arranged along a bottom portion of the reflector, where the heating element is positioned within the reflector with the reflector at least partially surrounding at least of portion of the heating element, the reflector having a front surface capable of projecting radiant heat out of the heater through the grill.
 19. A portable heater for providing radiant and convection heat as set forth in claim 18, further comprising: a blower mounted within the lower end of the housing, interposed between an air intake located a bottom of the hack portion and the air vent in the reflector far propelling air across the length of the reflector and the heating element.
 20. A portable heater for providing radiant and convection heat as set forth in claim 17, wherein when in the shipping configuration the potable heater is disposed in a package for shipment from a place of manufacturing to a place of sale. 